How did the million-dollar Apollo moon modules break up for science?

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The cost of each Apollo Moon module is approximately $ 149 million. So why were they torn apart in months?

Each month module costs approximately $ 149,000,000; Each spacecraft is adjusted to less than a billion dollars. The Apollo lunar module could not even enter the world atmosphere again, each of which had been abandoned or destroyed during the mission. The landing stages served as a launch pad for the ascent stages, so they all remained in the moon. On the other hand, the rise stages have come to a much more destructive end.

The Moon module started with the story of the rising stages, the story of NASA, which is doing Seismic experiments in the Moon. Seismology can tell scientists a lot about this body surface and internal structure by measuring how and how shock waves pass through a planetary body. Seismologists do this on Earth by studying earthquakes, so NASA decided to do the same kind of research on the moon.

As part of Moon Seismology experiments, the Apollo Lunar Surface Experiment Package or ALSEP, each Apollo reached the Moon with a landing mission. ALSEPs are designed to investigate the geophysical environment of the Moon, to answer its questions about its internal structure, its geometric shape, its tectonic activity and to shed light on the dynamic interaction with the Earth. In March 1966, the Bendix Systems Division was awarded to Bendix Corporation. The total budget was $ 17.3 million (about $ 126.5 million adjusted for inflation).

imageApollo 14 astronauts on training NASA

Each ALSEP was slightly different with a specific set of instruments designed for the landing area of ​​this task, but each package contained some kind of seismometer. They were designed to answer two specific questions: whether the moon has a molten core and how the Moon’s deep inner structure is.

In the next missions that brought all the ALSEPs to work, things became more sophisticated. Apollo 12, 14, 15 and 16 had a Moon Passive Seismic Test designed to determine the underlying surface properties of the Moon and measure the vibrations moving in the body. Seismic movements were recorded and returned to the receiving stations on the earth where they grew up to 10 million. Together, the four experiments allowed seismologists to identify the origin of the separators in three dimensions and record the effects of almost daily meteor effects. They were sensitive enough to record the surface effects of the sun heating of the moon surface at the beginning of a new moon.

Apollo 14 and 16, complementary Lunar Active Seismic Experiment in ALSEPs. This was an experiment designed to study the local area of ​​the Moon rather than the entire body, and its being active provided the source of its explosion for the instruments to be measured. These explosions were provided with two kinds of explosives. One was a series of small shotguns that were detonated by astronauts at certain points, according to ALSEP. The second explosion was much larger, and after the astronauts left the Moon, a mortar-type charge was launched by self-contained rockets, with four grenades being thrown. These active experiments are specifically designed to reveal any layer below about 1000 feet below the surface of the Moon.

imageApollo 14’s ALSEP on the Moon NASA   Apollo 17 added a Lunar Seismic Profiling Test to the mixture. Similar to the previous ALSEP passive seismometers, this used a ground network using four stations placed at the center and three points of the 89.91600 meters equilateral triangle. Explosives detonated by ground controllers generated seismic waves at varying forces for the instruments to be measured. The expenses made were instruments Passive Seismometer.

But NASA wanted more than just natural earthquakes and impacts. Any impactor that hit a known point removed data from the variables to obtain better results. And so the agency used what it had to force the results: it spent the rocket stages and the spacecraft. After firing the Apollo spacecraft into the translunar injection burn that sent it from Earth orbit to the Moon, the S-IVB upper stage of the Saturn V rocket was deliberately multiplied by the Moon, so that the vibrations could be measured by the seismometers of the previous tasks. on the surface.

Apollo 17 added a Lunar Seismic Profiling Test to the mixture. Similar to the previous ALSEP passive seismometers, this used a ground network using four stations placed at the center and three points of the 89.91600 meters equilateral triangle. Explosives detonated by ground controllers generated seismic waves at varying forces for the instruments to be measured. The expenses made were instruments Passive Seismometer.

But NASA wanted more than just natural earthquakes and impacts. Any impactor that hit a known point removed data from the variables to obtain better results. And so the agency used what it had to force the results: it spent the rocket stages and the spacecraft. After firing the translunar injection burn to the Apollo spacecraft from Earth orbit and the Moon, the S-IVB upper phase of the Saturn V rocket was intentionally multiplied by the Moon, so that the vibrations could be measured by the seismometers of previous missions. on the surface.

The rising stages of the lunar modules were also used for seismology. After the moon landing gear transferred everything that came back to Earth from the moon module and turned it off, the useless spacecraft is now bypassed and steered by Mission Control to impress the Moon’s surface at a certain point close to an ALSE. One of these controlled crashes gave surprisingly strange results. When the Moon module of Apollo 12 hit Intrepid’s moon surface, the resulting shock wave vibrated on the Moon for more than 55 minutes. Scientists ultimately remained dry until the Moon, the continuous spread of the wave; Dry rocks did not dampen the waves as efficiently as on Earth.

The three exceptions were Apollo 9, Apollo 10 and Apollo 13. Apollo 9 was a Earth orbital mission, so the Moon module burned in Earth’s atmosphere. Apollo 10 launches the Moon module Snoopy into the orbit of the sun today. Apollo 13 used the Moon module Aquarius as a lifeguard boat on the way back to earth, and burned it in the atmosphere to blow up again.

During the Apollo period, the network of seismometers, which recorded more than 1,700 meteorological effects, revealed that the stresses caused by the changes in the tides of the moon produce up to 300 monthly laps each year, consisting of about 300 different areas each year. These experiments helped scientists to determine that the Moon had a structure similar to Earth: an average 31 mil thick shell rich in mineral plagioclase, a mantle made of olivine and pyroxene, and a relatively small core, mostly iron and sulfur. .

Powered by a small radioisotope thermoelectric generator, each ALSEP was designed to operate in a local lunar environment at least one year after the crew left the surface of the crew. But it took longer than eight years before NASA had been permanently shut down in September 1977. Of course, they are still there along with the remains of the S-IVB and moon modules for future archaeologists.

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